SpaceX picking up the pace......
https://spaceflightnow.com/2017/05/1...hed-by-spacex/
A Boeing-built satellite on the way to join Inmarsat’s globe-spanning network geared to beam Internet and data transmission capacity to airline passengers, maritime crews and military personnel flew into orbit Monday from NASA’s Kennedy Space Center in Florida aboard an expendable Falcon 9 rocke. The satellite is the fourth member of Inmarsat’s broadband communications fleet, a $1.6 billion initiative named Global Xpress conceived to connect aircraft, ships at sea, and mobile users on land with through an umbrella of worldwide Ka-band beams.
The two-stage rocket, towering 229 feet (70 meters) tall, was stripped of recovery hardware to give the 6.7-ton Inmarsat 5 F4 payload the boost it needed toward an eventual circular geostationary orbit 22,300 miles (35,800 kilometers) over the equator.......
The first stage engines turned off around T+plus 2 minutes, 45 seconds, and the booster stage detached to fall into the Atlantic Ocean on a destructive plunge. The heavy weight of the Inmarsat 5 F4 satellite, which weighed 13,417 pounds (6,086 kilograms) at liftoff, required all of the Falcon 9’s energy, leaving no propellant left over for the first stage to slow down for a landing........
The on-target deployment gave SpaceX its second successful launch in two weeks, after a Falcon 9 rocketed into orbit with a top secret U.S. government spy payload May 1*......
Monday’s launch debuted an upgrade to the Falcon 9 rocket’s second stage intended to speed up fueling during launch countdowns, allowing liquid oxygen and helium pressurant to be simultaneously loaded into the launcher.
Investigators blamed a Falcon 9 rocket explosion at Cape Canaveral’s pad 40 last September on voids in the skin of high-pressure helium tanks immersed in super-cold liquid oxygen inside the launcher’s second stage. Liquid oxygen became trapped, and perhaps froze, in the openings, leading to friction that eventually caused the rocket to explode, destroying an Israeli-owned communications satellite during a countdown rehearsal. After an engineering inquiry settled on a probable cause for the mishap, SpaceX said future countdown sequences would change to load helium into the rocket before liquid oxygen, a modification the company said would avoid the problem. At the same time, SpaceX said it would make hardware changes to the rocket to permanently fix the helium tank concern.
Those unspecified safety upgrades made their way into the Falcon 9 that launched Monday. A SpaceX official said the next two Falcon 9 flights in June will not have the helium tank modification, but then all future rockets will incorporate the change.
SpaceX ground crews are preparing for four more launches by the end of June, with the next Falcon 9 flight slated for June 1 with a Dragon supply ship to ferry experiments and equipment to the International Space Station. Liftoff of the Dragon capsule — the first SpaceX cargo craft to be reused after a previous space station mission — is scheduled for approximately 5:55 p.m. EDT (2155 GMT) June 1 from pad 39A.
Another Falcon 9 rocket is being primed for blastoff from the Kennedy Space Center on June 15 with BulgariaSat 1, Bulgaria’s first communications satellite. That launcher will fly with a previously-used first stage, the second time SpaceX will have re-flown a Falcon 9 booster.
Two more Falcon 9 missions in late June will launch from the Kennedy Space Center and Vandenberg Air Force Base in California.
The Intelsat 35e telecom satellite, a trans-Atlantic video, data and broadband relay station, has a launch window some time between June 26 and July 2 from Florida, an Intelsat spokesperson said Monday.
The second batch of 10 next-generation satellites for Iridium’s mobile telephone and data messaging constellation is supposed to launch June 29 from California.
*1st May booster landed back at Canaveral successfully. Excellent video of recovery included below.